Y-kapellasite (Y3Cu9(OH)19Cl8), which hosts an original anisotropic kagome sublattice, is a promising candidate for studying elusive and complex correlated physics. It exhibits a theoretically predicted in-plane (1/3,1/3) magnetic order [1] but its magnetic interaction values place it close to a phase boundary to a spin liquid state [2]. Our μSR measurements under hydrostatic pressure demonstrate the complete suppression of static magnetism in favor of a fully dynamical ground state at 2.3~GPa. Complementary high-pressure x-ray and optical phonon measurements reveal a gradual reduction of the kagome anisotropy, enhancing magnetic frustration without structural transitions. Our results establish Y-kapellasite as a rare clean kagome model in which long-range order is suppressed by pressure-tuned frustration, the first fingerprint for the realization of a quantum spin liquid without strong disorder.
@article{arxiv.2502.09733,
title = {Emergence of a Fluctuating Ground State in Y-kapellasite under Pressure},
author = {Dipranjan Chatterjee and Petr Doležal and Federico Abbruciati and Tobias Biesner and Katharina M. Zoch and Rustem Khasanov and Shams Sohel Islam and Guratinder Kaur and Seulki Roh and Francesco Capitani and Joao Elias F. S. Rodrigues and Gaston Garbarino and Cornelius Krellner and Philippe Mendels and Edwin Kermarrec and Martin Dressel and Björn Wehinger and Andrej Pustogow and Fabrice Bert and Pascal Puphal},
journal= {arXiv preprint arXiv:2502.09733},
year = {2026}
}